The life he was used to( has changed )greatly since 1992,为什么括号里是has changed ,而不填have changed ,change changing

The life he was used to( has changed )greatly since 1992,
为什么括号里是has changed ,而不填have changed ,change changing

第一 主语是 the life .he was used to是The life 的修饰语而已 ,所以 不用have 用has.
第二 since 就是完成式的标志 当然是不能用不适合时态的 changes 和 is/was changing
更何况是完全错误的change和 changing

自从1992年以来，比起他过去所过的生活，他现在过的生活发生了很大的改变。 没问题. The life he was used to has changed greatly since 1992. 自